Nutritional composition containing oligosaccharide mixture

ABSTRACT

A nutritional composition for administration to an infant which composition comprises, on a dry matter basis, from 2.5 to 15.0 wt % of an oligosaccharide mixture consisting of N-acetylated oligosaccharide(s), galacto-oligasaccharide(s) and sialylated oligosaccharide(s) with the proviso that the composition comprises at least 0.02 wt % of an N-acetylated oligosaccharide, at least 2.0 wt % of a galacto-oligosaccharide and at least 0.04 wt % of a sialylated oligosaccharide and that the N-acetylated oligosaccharide(s) comprise 0.5 to 4.0% of the oligosaccharide mixture, the galacto- oligosaccharide(s) comprise 92.0 to 98.5% of the oligosaccharide mixture and the sialylated oligosacchardide(s) comprise 1.0 to 4.0% of the oligosaccharide mixture. The composition is useful for administration to an infant in the first six months of life to reduce the risk of obesity later in life.

PRIORITY CLAIM

This application is a divisional of U.S. application Ser. No.13/003,467, filed Jan. 10, 2011, which is a National Stage ofInternational Application No. PCT/EP2009/057656, filed on Jun. 19, 2009,which claims priority to European Patent Application No. 08159900.3,filed on Jul. 8, 2008, the entire contents of which are beingincorporated herein by reference.

FIELD OF THE INVENTION

The invention relates to a nutritional composition such as an infantformula supplemented with an oligosaccharide mixture.

BACKGROUND

The human colon is colonised with a wide range of bacteria that haveboth positive and negative effects on gut physiology as well as havingother systemic influences. Predominant groups of bacteria found in thecolon include bacteroides, bifidobacteria, eubacteria, clostridia andlactobacilli. The bacteria present have fluctuating activities inresponse to substrate availability, redox potential, pH, O₂ tension anddistribution in the colon. In general intestinal bacteria can be dividedinto species that exert either potentially harmful or beneficial effectson the host. Pathogenic effects (which may be caused by clostridia orbacteroides, for example) include diarrhoea, infections, liver damage,carcinogenesis and intestinal putrefaction. Health-promoting effects maybe caused by the inhibition of growth of harmful bacteria, stimulationof immune functions, improving digestion and absorption of essentialnutrients and synthesis of vitamins. An increase in numbers and/oractivities of bacterial groups (such as Bifrdobacterium andLactobacillus) that may have health promoting properties is desirable.

As far as infants specifically are concerned, immediately before birth,the gastro-intestinal tract of a baby is thought to be sterile. Duringthe process of birth, it encounters bacteria from the digestive tractand skin of the mother and starts to become colonised. Large differencesexist with respect to the composition of the gut microbiota in responseto the infant's feeding. The faecal flora of breast-fed infants includesappreciable populations of Bifidobacteria with some Lactobacillusspecies, whereas formula-fed infants have more complex microbiota, withBifidobacteria, Bacteroides, Clostridia and Streptococci all usuallypresent. After weaning, a pattern of gut microbiota that resembles theadult pattern becomes established.

One approach to promote the numbers and/or activities of beneficialbacteria in the colon is the addition of prebiotics to foodstuffs. Aprebiotic is a non-digestible food ingredient that beneficially affectsthe host by selectively stimulating the growth and/or activity of one ora limited number of bacteria in the colon, and thus improves hosthealth. Such ingredients are non-digestible in the sense that they arenot broken down and absorbed in the stomach or small intestine and thuspass intact to the colon where they are selectively fermented by thebeneficial bacteria. Examples of prebiotics include certainoligosaccharides, such as fructooligosaccharides (FOS) andgalactooligosaccharides (GOS).

Human milk is known to contain a larger amount of indigestibleoligosaccharides than most other animal milks. In fact, indigestibleoligosaccharides represent the third largest solid component (afterlactose and lipids) in breast milk, occurring at a concentration of12-15 g/l in colostrum and 5-8 g/l in mature milk. Human milkoligosaccharides are very resistant to enzymatic hydrolysis, indicatingthat these oligosaccharides may display essential functions not directlyrelated to their calorific value.

Mother's milk is recommended for all infants. However, in some casesbreast feeding is inadequate or unsuccessful for medical reasons or themother chooses not to breast feed. Infant formulas have been developedfor these situations. As the composition of human milk becomes betterunderstood, it has also been proposed to add prebiotics to infantformula. Various infant formulas supplemented with prebiotics such asmixtures of fructooligosaccharides and galactooligosaccharides forexample are commercially available. However, such mixtures approximateonly roughly the mixture of oligosaccharides in human milk. Over 100different oligosaccharide components have been detected in human milksome of which have not been so far detected in animal milks such asbovine milk at all or have been detected only in small quantities.Examples of classes of human milk oligosaccharide that are present inbovine milk and colostrum only in very small quantities or not at allare sialylated and fucosylated oligosaccharides.

US Patent Application No. 2003/0129278 describes an oligosaccharidemixture based on oligosaccharides produced from one or several animalmilks which is characterized in that it comprises at least twooligosaccharide fractions which are each composed of at least twodifferent oligosaccharides, with free lactose not pertaining thereto.The total spectrum of the oligosaccharides present in theoligosaccharide mixture differs from those present in the animal milk oranimal milks from which the oligosaccharide fractions were extracted.Further a) if said oligosaccharides are extracted from only one animalmilk, the proportion of neutral oligosaccharides to acidic (sialylated)oligosaccharides is 90-60: 10-40 weight %, or b) if saidoligosaccharides are extracted from at least two animal milks, theoligosaccharides extracted from two different animal milks each make up10 weight % of the total amount of oligosaccharides present in theoligosaccharide mixture.

WO2007/090894 describes an oligosaccharide mixture which comprises 5 to70 wt % of at least one N-acetylated oligosaccharide, 20 to 90 wt % ofat least one neutral galacto-oligosaccharide and 5 to 50 wt % of atleast one sialylated oligosaccharide.

Most research interest has focused on the fermentability andbifidogenicity of oligosaccharide prebiotics. However, in vitro studieshave shown that a number of oligosaccharide prebiotics mimic theeukaryotic cell surface receptors to which virulent bacteria adhere aspart of the pathogenicity process (Shoaf et al, 2006). Further,trans-galacto-oligosaccharides have been found to enhance the protectiveabilities of Bifidobacterium breve in mice infected with Salmonellaenterica (Asahara et al, 2001). Other potential benefits of prebioticshave also been investigated in adults including immunomodulatoryproperties, bone mineralisation and cardiovascular effects. Studies onneonates and infants have concentrated on the abilities ofoligosaccharides to increase faecal Bifidobacteria populations.Surprisingly few studies have been carried out on disease prevention orpossible treatment benefits of prebiotic use in infants. Colostrum onlyin very small quantities or not at all are sialylated and fucosylatedoligosaccharides.

US Patent Application No. 2003/0129278 describes an oligosaccharidemixture based on oligosaccharides produced from one or several animalmilks which is characterized in that it comprises at least twooligosaccharide fractions which are each composed of at least twodifferent oligosaccharides, with free lactose not pertaining thereto.The total spectrum of the oligosaccharides present in theoligosaccharide mixture differs from those present in the animal milk oranimal milks from which the oligosaccharide fractions were extracted.Further a) if said oligosaccharides are extracted from only one animalmilk, the proportion of neutral oligosaccharides to acidic (sialylated)oligosaccharides is 90-60: 10-40 weight %, or b) if saidoligosaccharides are extracted from at least two animal milks, theoligosaccharides extracted from two different animal milks each make up10 weight % of the total amount of oligosaccharides present in theoligosaccharide mixture.

WO2007/090894 describes an oligosaccharide mixture which comprises 5 to70 wt % of at least one N-acetylated oligosaccharide, 20 to 90 wt % ofat least one neutral galacto-oligosaccharide and 5 to 50 wt % of atleast one sialylated oligosaccharide.

Most research interest has focused on the fermentability andbifidogenicity of oligosaccharide prebiotics. However, in vitro studieshave shown that a number of oligosaccharide prebiotics mimic theeukaryotic cell surface receptors to which virulent bacteria adhere aspart of the pathogenicity process (Shoaf et al, 2006). Further,trans-galacto-oligosaccharides have been found to enhance the protectiveabilities of Bifidobacterium breve in mice infected with Salmonellaenterica (Asahara et al, 2001). Other potential benefits of prebioticshave also been investigated in adults including immunomodulatoryproperties, bone mineralisation and cardiovascular effects. Studies onneonates and infants have concentrated on the abilities ofoligosaccharides to increase faecal Bifidobacteria populations.Surprisingly few studies have been carried out on disease prevention orpossible treatment benefits of prebiotic use in infants.

In recent years, concerns about overweight and obesity in the adultpopulation have grown substantially to the point where obesity is themost burdensome and costly nutritional condition worldwide. As a result,attention is starting to focus on the significance of developmentsduring infancy for the risk of obesity later in life with particularregard to the extent to which growth during infancy may be a predictorof later adiposity. Some commentators believe that weight gain in thefirst six months of life is primarily a gain in fat; if weight gain ininfancy is indeed predictive of later adiposity, it follows that gainsin adiposity in infancy may need to be carefully monitored to reduce therisk of obesity of the individual later in life (Gilman M. W., “Thefirst months of life: a critical period for development of obesity” Am JClin Nutr 2008;87: 1587-9).

SUMMARY

The present inventors have surprisingly discovered that theadministration of a mixture of prebiotic oligosaccharides comprisinggalacto-oligosaccharides with small quantities of more complexoligosaccharide species such as sialylated oligosaccharides andnon-sialylated oligosaccharides including at least one N-acetyl group togerm-free mice inoculated with a human baby microbiota modulates lipidmetabolism by reducing lipogenesis and promoting fatty acidbeta-oxidation as compared with a control group not receiving theoligosaccharide mixture.

Accordingly, the present invention provides the use of an N-acetylatedoligosaccharide, a galacto-oligosaccharide and a sialylatedoligosaccharide in the manufacture of a nutritional composition foradministration to an infant in the first six months of life to reducethe risk of obesity later in life.

The invention extends to a nutritional composition for administration toan infant which composition comprises, on a dry matter basis, from 2.5to 15.0 wt % of an oligosaccharide mixture consisting of N-acetylatedoligosaccharide(s), galacto-oligosaccharide(s) and sialylatedoligosaccharide(s) with the proviso that the composition comprises atleast 0.02 wt % of an N-acetylated oligosaccharide, at least 2.0 wt % ofa galacto-oligosaccharide and at least 0.04 wt % of a sialylatedoligosaccharide and that the N-acetylated oligosaccharide(s) comprise0.5 to 4.0% of the oligosaccharide mixture, thegalacto-oligosaccharide(s) comprise 92.0 to 98.5% of the oligosaccharidemixture and the sialylated oligosaccharide(s) comprise 1.0 to 4.0% ofthe oligosaccharide mixture.

The benefits of a nutritional composition according to the inventionextend to reduction of lipogenesis and higher beta-oxidation of fattyacids.

In an embodiment the oligosaccharide mixture may be derived from animalmilk, such as one or more of cows' milk, goats' milk or buffalo milk.

Preferably, the nutritional composition is an infant formula, but it maybe any food or drink consumed by infants in the first few months of lifeincluding a therapeutic nutritional composition meeting the requirementsof the EU regulations governing Foods for Special Medical Purposes(FSMP).

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 shows a comparison of the concentrations of triglycerides in thelivers of mice from the control group (n=9) and mice from theexperimental group (n=10) displayed using box-and-whisker plots.

FIG. 2 shows a comparison of the expression of microsomal triglyceridetransfer protein (MTTP) and fatty acid synthase (FAS) in the livers ofmice from the control group (n=9) and the experimental group (n=10)displayed using box-and-whisker plots.

DETAILED DESCRIPTION

In this specification, the following expressions have the meaningsassigned to them below:

“galacto-oligosaccharide” means an oligosaccharide comprising two ormore galactose molecules which has no charge and no N-acetyl residue;

“infant” means a child under the age of 12 months;

“infant formula” means a foodstuff intended for the complete nutritionof infants during the first four to six months of life. (Article 1.2 ofthe European Commission Directive 91/321/EEC of 14 May 1991 on infantformulae and follow-on formulae);

“N-acetylated oligosaccharide” means an oligosaccharide having anN-acetyl residue;

“oligosaccharide” means a carbohydrate having a degree of polymerisation(DP) ranging from 2 to 20 inclusive but not including lactose;

“prebiotic” means a selectively fermented ingredient that allowsspecific changes, both in the composition and/or activity in thegastrointestinal microbiota that confers benefits upon host well-beingand health (Bouhnik et al, 2004);

“sialylated oligosaccharide” means an oligosaccharide having a sialicacid residue with associated charge.

Suitable N-acetylated oligosaccharides include GalNAcα1,3Galβ1,4Glc andGalβ1,6GalNAcα1,3Galβ1,4Glc. The N-acetylated oligosaccharides may beprepared by the action of glucosaminidase and/or galactosaminidase onN-acetyl-glucose and/or N-acetyl galactose. Equally, N-acetyl-galactosyltransferases and/or N-acetyl-glycosyl transferases may be used for thispurpose. The N-acetylated oligosaceharides may also be produced byfermentation technology using respective enzymes (recombinant ornatural) and/or microbial fermentation. In the latter case the microbesmay either express their natural enzymes and substrates or may beengineered to produce respective substrates and enzymes. Singlemicrobial cultures or mixed cultures may be used. N-acetylatedoligosaccharide formation can be initiated by acceptor substratesstarting from any degree of polymerisation (DP) from DP=1 onwards.Another option is the chemical conversion of keto-hexoses (e.g.fructose) either free or bound to an oligosaccharide (e.g. lactulose)into N-acetylhexosamine or an N-acetylhexosamine containingoligosaccharide as described in Wrodnigg, T. M.; Stutz, A. E. (1999)Angew. Chem. Int. Ed. 38:827-828.

Suitable galacto-oligosaccharides include Galβ1,6Gal, Galβ1,6Galβ1,4GlcGal β1,6Galβ1,6Glc, Galβ1,3Galβ1,3Glc, Galβ1,3Galβ1,4Glc,Galβ1,6Galβ1,6Galβ1,4Glc, Galβ1,6Galβ1,3Galβ1,4Glc,Galβ1,3Galβ1,6Gal1,4Glc, Galβ1,3Galβ1,3Galβ1,4Glc, Galβ1,4Galβ1,4Glc andGalβ1,4Galβ1,4Galβ1,4Glc. Synthesised galacto-oligosaccharides such asGalβ1,6Galβ1,4Glc Galβ1,6Galβ1,6Glc, Galβ1,3Galβ1,4Glc,Galβ1,6Galβ1,6Galβ1,4Glc, Galβ1,6Galβ1,3Galβ1,4Glc andGalβ1,3Galβ1,6Galβ1,4Glc, Galβ1,4Galβ1,4Glc and Galβ1,4Galβ1,4Galβ4Glcand mixtures thereof are commercially available under the trade marksVivinal® and Elix'or®. Other suppliers of oligosaccharides are DextraLaboratories, Sigma-Aldrich Chemie GmbH and Kyowa Hakko Kogyo Co., Ltd.Alternatively, specific glycoslytransferases, such asgalactosyltransferases may be used to produce neutral oligosaccharides.

Suitable sialylated oligosaccharidesincludeNeuAcα2,3Galβ1,4Glc andNeuAcα2,6Galβ1,4Glc. These sialylated oligosaccharides may be isolatedby chromatographic or filtration technology from a natural source suchas animal milks. Alternatively, they may also be produced bybiotechnology using specific sialyltransferases either by enzyme basedfermentation technology (recombinant or natural enzymes) or by microbialfermentation technology. In the latter case microbes may either expresstheir natural enzymes and substrates or may be engineered to producerespective substrates and enzymes. Single microbial cultures or mixedcultures may be used. Sialyl-oligosaccharide formation can be initiatedby acceptor substrates starting from any degree of polymerisation (DP)from DP=1 onwards.

Preferably, the nutritional composition comprises 3.0 to 12.0% of theoligosaccharide mixture, more preferably from 4.0 to 7.0% of theoligosaccharide mixture.

The nutritional composition preferably comprises at least 0.03 wt % ofan N-acetylated oligosaccharide, at least 3.0 wt % of agalacto-oligosaccharide and at least 0.08 wt % of a sialylatedoligosaccharide, more preferably at least 0.04 wt % of an N-acetylatedoligosaccharide, at least 4.0 wt % of a galacto-oligosaccharide and atleast 0.09 wt % of a sialylated oligosaccharide.

A nutritional composition according to the invention preferably alsocomprises at least one probiotic bacterial strain. A probiotic is amicrobial cell preparation or components of microbial cells with abeneficial effect on the health or well-being of the host. Suitableprobiotic bacterial strains include Lactobacillus rhamnosus ATCC 53103obtainable from Valio Oy of Finland under the trade mark LGG,Lactobacillus rhamnosus CGMCC 1.3724, Lactobacillus paracasei CNCM1-2116, Lactobacillus reuteri ATCC 55730 and Lactobacillus reuteri DSM17938 obtainable from Biogaia, Lactobacillus fermentum VRI 003,Streptococcus salivarius DSM 13084 sold by BLIS Technologies Limited ofNew Zealand under the designation K12, Bifidobacterium lactis CNCM1-3446 sold inter alia by the Christian Hansen company of Denmark underthe trade mark Bb12, Bifidobacterium longum ATCC BAA-999 sold byMorinaga Milk Industry Co. Ltd. of Japan under the trade mark BB536, thestrain of Bifidobacterium breve sold by Danisco under the trade markBb-03, the strain of Bifidobacterium breve sold by Morinaga under thetrade mark M-16V, the strain of Bifidobacterium ifantis sold by Procter& Gamble Co. under the trade mark Bifantis and the strain ofBifidobacterium breve sold by Institut Rosell (Lallemand) under thetrade mark R0070. The probiotic may be added in an amount between 10e3and 10e12 cfu/g powder, more preferably between 10e7 and 10e12 cfu/gpowder.

Preferably the nutritional composition according to the invention is aninfant formula. The general composition of an infant formula accordingto the invention will now be described by way of example.

The formula contains a protein source. The type of protein is notbelieved to be critical to the present invention provided that theminimum requirements for essential amino acid content are met andsatisfactory growth is ensured. Thus, protein sources based on whey,casein and mixtures thereof may be used as well as protein sources basedon soy. As far as whey proteins are concerned, the protein source may bebased on acid whey or sweet whey or mixtures thereof and may includealpha-lactalbumin and beta-lactoglobulin in whatever proportions aredesired.

The proteins may be intact or hydrolysed or a mixture of intact andhydrolysed proteins. It may be desirable to supply partially hydrolysedproteins (degree of hydrolysis between 2 and 20%), for example forinfants believed to be at risk of developing cows' milk allergy. Ifhydrolysed proteins are required, the hydrolysis process may be carriedout as desired and as is known in the art. For example, a whey proteinhydrolysate may be prepared by enzymatically hydrolysing the wheyfraction in one or more steps. If the whey fraction used as the startingmaterial is substantially lactose free, it is found that the proteinsuffers much less lysine blockage during the hydrolysis process. Thisenables the extent of lysine blockage to be reduced from about 15% byweight of total lysine to less than about 10% by weight of lysine; forexample about 7% by weight of lysine which greatly improves thenutritional quality of the protein source.

An infant formula according to the present invention contains acarbohydrate source. Any carbohydrate source conventionally found ininfant formulae such as lactose, saecharose, maltodextrin, starch andmixtures thereof may be used although the preferred source ofcarbohydrates is lactose. Preferably the carbohydrate sources contributebetween 35 and 65% of the total energy of the formula.

An infant formula according to the present invention contains a sourceof lipids. The lipid source may be any lipid or fat which is suitablefor use in infant formulas. Preferred fat sources include palm olein,high oleic sunflower oil and high oleic safflower oil. The essentialfatty acids linoleic and α-linolenic acid may also be added as may smallamounts of oils containing high quantities of preformed arachidonic acidand docosahexaenoic acid such as fish oils or microbial oils. In total,the fat content is preferably such as to contribute between 30 to 55% ofthe total energy of the formula. The fat source preferably has a ratioof n-6 to n-3 fatty acids of about 5:1 to about 15:1; for example about8:1 to about 10:1.

The infant formula will also contain all vitamins and mineralsunderstood to be essential in the daily diet and in nutritionallysignificant amounts. Minimum requirements have been established forcertain vitamins and minerals. Examples of minerals, vitamins and othernutrients optionally present in the infant formula include vitamin A,vitamin 131, vitamin B2, vitamin B6, vitamin B12, vitamin E, vitamin K,vitamin C, vitamin D, folic acid, inositol, niacin, biotin, pantothenicacid, choline, calcium, phosphorous, iodine, iron, magnesium, copper,zinc, manganese, chloride, potassium, sodium, selenium, chromium,molybdenum, taurine, and L-carnitine. Minerals are usually added in saltform. The presence and amounts of specific minerals and other vitaminswill vary depending on the intended infant population.

If necessary, the infant formula may contain emulsifiers and stabiliserssuch as soy lecithin, citric acid esters of mono- and di-glycerides, andthe like.

The infant formula may optionally contain other substances which mayhave a beneficial effect such as lactoferrin, nucleotides, nucleosides,and the like.

Finally, the formula will contain from 2.5 to 15.0 wt % of anoligosaccharide mixture consisting of N-acetylated oligosaccharide(s),galacto-oligosaccharide(s) and sialylated oligosaccharide(s) in amountsof at least 0.02 wt % of an N-acetylated oligosaccharide, at least 2.0wt % of a galacto-oligosaccharide and at least 0.04 wt % of a sialylatedoligosaccharide, the N-acetylated oligosaccharide(s) comprising 0.5 to4.0% of the oligosaccharide mixture, the galacto-oligosaccharide(s)comprising 92.0 to 98.5% of the oligosaccharide mixture and thesialylated oligosaccharide(s) comprising 1.0 to 4.0% of theoligosaccharide mixture.

The infant formula may be prepared by blending together the proteinsource, the carbohydrate source and the fat source in appropriateproportions. Emulsifiers may be added if desired. Vitamins and mineralsmay be added at this point but are usually added later to avoid thermaldegradation. Any lipophilic vitamins, emulsifiers and the like may bedissolved into the fat source prior to blending. Water, preferably waterwhich has been subjected to reverse osmosis, may then be mixed in toform a liquid mixture.

The liquid mixture may then be thermally treated to reduce bacterialloads. For example, the liquid mixture may be rapidly heated to atemperature in the range of about 80° C. to about 110° C. for about 5seconds to about 5 minutes. This may be carried out by steam injectionor by heat exchanger, e.g. a plate heat exchanger.

The liquid mixture may then be cooled to about 60° C. to about 85° C.,for example by flash cooling. The liquid mixture may then behomogenised, for example in two stages at about 7 MPa to about 40 MPa inthe first stage and about 2 MPa to about 14 MPa in the second stage. Thehomogenised mixture may then be further cooled to add any heat sensitivecomponents such as vitamins and minerals. The pH and solids content ofthe homogenised mixture is conveniently standardised at this point.

The homogenised mixture is transferred to a suitable drying apparatus,such as a spray drier or freeze drier, and converted to powder. Thepowder should have a moisture content of less than about 5% by weight.

The oligosaccharides may be added directly to the infant formula by drymixing.

Preferably, the infant formula according to the invention is fed to thebaby at every feed.

The invention will now be illustrated by reference to the followingexamples.

EXAMPLE 1

An example of the composition of an infant formula according to thepresent invention is given below.

Nutrient per 100 kca1 per litre Energy (kcal) 100 670 Protein (g) 1.8312.3 Fat(g) 5.3 35.7 Linoleic acid (g) 0.79 5.3 A-Linolenic acid (mg)101 675 Lactose (g) 11.2 74.7 Galacto-oli osaccharides (g) 1.1 6.8N-acetylated oligosaccharides (g) 0.027 0.055 Sialylatedoligosaccharides (g) 0.027 0.134 Minerals (g) 0.37 2.5 Na (mg) 23 150 K(mg) 89 590 Cl (mg) 64 430 Ca (mg) 62 410 P (mg) 31 210 Mg (mg) 7 50 Mn(μg) 8 50 Se (μg) 2 13 Vitamin A (μg RE) 105 700 Vitamin D (μg) 1.5 10Vitamin E (mg TE) 0.8 5.4 Vitamin K1 (μg) 8 54 Vitamin C (mg) 10 67Vitamin B1 (mg) 0.07 0.47 Vitamin B2 (mg) 0.15 1.0 Niacin (mg) 1 6.7Vitamin B6 (mg) 0.075 0.50 Folic acid (μg) 9 60 Pantothenic acid (mg)0.45 3 Vitamin B12 (μg) 0.3 2 Biotin (μg) 2.2 15 Choline (mg) 10 67 Fe(mg) 1.2 8 I (μg) 15 100 Cu (mg) 0.06 0.4 Zn (mg) 0.75 5

EXAMPLE 2

The effect of a nutritional composition according to the invention onlipogenesis and fat oxidation was investigated in germ free miceinoculated with a human baby microbiota (HBM).

Experimental design. A total of 19 C3H female germ-free mice (CharlesRiver, France) were housed under the same environmental conditions andwere fed with a standard semi-synthetic irradiated rodent diet (Reeveset al, 1993). At 8 weeks of age, the germ-free mice received a singledose of human baby microbiota (HBM) bacteria mixture and were assignedrandomly to 2 groups which followed different nutritional interventionsover a 2 week period. The HBM composition was previously reported(Martin et al, 2007). One group was kept as control, and was fed with a‘basal mix’ diet containing in composition 2.5% of a glucose-lactose mix(1.25% each) (control group, n=9). A second group of mice was fed with adiet containing 0.11% N-acetylated oligosaccharides, 2.7%galacto-oligosaccharides and 0.11% sialylated oligosaccharides(experimental group, n=10).

Sample Collection and analytical measures Morning spot urines, bloodplasma, and intact liver tissues were collected upon animal autopsy andsnap-frozen prior to metabonomic analysis. Metabonomics using highresolution spectroscopic methods with subsequent multivariatestatistical analyses is a well-established strategy for differentialmetabolic pathway profiling and assessment of dietary interventioneffects and efficacy (Martin et al, 2008; Nicholson et al, 2005; Rezziet al, 2007b; Rezzi et al, 2007a; Stella et al, 2006). The metabolicprofiles were mined with multivariate analytical methods to recovermetabolic probes of oligosaccharide intervention, which serve asreference for describing and predicting groups of animals according totreatments (Table 1).

Results

Table 1 and FIG. 1 show that use of a nutritional composition accordingto the invention reduced triglyceride concentration in the liver. Thecontrol and experimental groups were compared using unpaired Student'st-test and the difference was statistical significant at 95% confidencelevel. Table 1 and FIG. 2 show that use of a nutritional compositionaccording to the invention also reduced lipogenesis and triacylglycerolincorporation into lipoproteins in the liver, the measure Delta CTplotted on the y-axis in FIG. 2 being the difference between thethreshold cycle of the gene of interest and that of the endogenousreference gene. The decrease in expression levels in animals in theexperimental group was significant at 99.9% confidence level when usingunpaired Student's t-test. Higher urinary excretion of carnitine andacetyl-carnitine further showed enhancement of fatty acid oxidation(Table 1). These results together with higher betaine homocysteinemethyl transferase metabolic activity in the liver (Table 1) indicatedhigher secretion of nascent lipoprotein particles, smaller in size andcarrying less triacylglycerols.

Measures of triglycerides and activity of microsomal triglyceridetransfer protein (MTTP) and fatty acid synthase (FAS) in the livers ofmice in the control and experimental groups confirmed that mice in theexperimental group had decreased hepatic triglycerides, lipogenicactivities (FAS) and incorporation of triglycerides into lipoproteins(MTTP) (FIG. 2,).

The higher concentrations of carnitine and acetyl-carnitine and lowerlevels of L-aminoadipate and a-keto-isocaproate in urine of micereceiving prebiotic provide further evidence of a shift in lipidmetabolism (Kliewer et al, 1997). In particular, carnitine is awell-characterized cofactor required for transformation of freelong-chain fatty acids into acylcarnitines and their subsequenttransport into the mitochondria) matrix, where they undergo β-oxidation(Bremer, 1983). Therefore, the results indicate enhancement of fattyacid oxidation (Table 1).

These results show liver-specific changes in betaine hornocysteinemethyl transferase (BHMT), metabolic pathways that closely interconnectcholine, betaine and the formation of methionine from hornocysteine(Niculescu & Zeisel, 2002). Increased expression of BHMT has beenreported as a potential mechanism contributing to higher ApoB secretionavailable for VLDL assembly (Sparks et al, 2006). Moreover, previousstudies described that certain complex carbohydrate (starch) dietsresult in higher secretion of nascent VLDL particles, smaller in sizeand carrying less triacylglycerols, and increased VLDL apo B fractionalcatabolic rates (Fernandez et al, 1996). Therefore, enhanced BHMTmetabolism and lower MTTP activities indicate higher apo B apoproteinssynthesis and decreased transfer of lipids into nascent lipoproteins,which suggests the involvement of a similar mechanism in response tothis intervention.

TABLE 1 Influential metabolites describing prebiotic metabolic effectsin plasma, liver and urine Metabolite Control Group Experimental GroupPlasma Q_(y) ² = 29%, R_(x) ² = 86% Lipoproteins 0.5 ± 0.2  0.4 ± 0.1Liver Q_(Y) ² = 36%, R_(x) ² = 46% Betaine 1.6 ± 0.3  2.5 ± 0.2***Choline 0.5 ± 0.2  1.1 ± 0.2*** DMG 0.06 ± 0.02 0.19 ± 0.05*** Tri 1eerides 3.6 ± 1.3  2.1 ± 0.4* Phosphocholine 1.7 ± 0.3  2.4 ± 0.3***Sarcosine 0.14 ± 0.03 0.18 ± 0.02* Urine Q_(Y) ² = 70%, R_(x) ² = 49%Carnitine  0.3 ± 0.06  5.2 ± 1.3*** N-acetyl-carnitine  017 ± 0.02  1.3± 0.3*** α-keto-isocaroate 1.3 ± 0.3  0.9 ± 0.1 * α-aminoadiate 0.33 ±0.05 0.19 ± 0.02***

O-PLS models were generated with I predictive component, and 2orthogonal components to discriminate between 2 groups of mice. TheR_(x) ² value shows how much of the variation in the dataset X isexplained by the model. The Q_(Y) ² value represents the predictabilityof the models, and relates to its statistical validity. Data arepresented as area normalized intensities (a.u.) of representativemetabolite signals as means±standard deviation (SD). The values for theHBM mice supplemented with prebiotics were compared to HBM control mice,*, and *** designate significant difference at 95% and 99.9% confidencelevel, respectively.

The invention is claimed as follows:
 1. A method for reducing the riskof obesity later in life to an infant comprising the steps ofadministering a nutritional composition comprising an N-acetylatedoligosaccharide, a galacto-oligosaccharide and a sialylatedoligosaccharide to an infant in the first six months of life.
 2. Methodfor reducing lipogenesis in an infant comprising the steps ofadministering a nutritional composition comprising an N-acetylatedoligosaccharide, a galacto-oligosaccharide and a sialylatedoligosaccharide to an infant in the first six months of life.
 3. Methodfor promoting beta-oxidation of fatty acids by an infant comprising thesteps of administering a nutritional composition comprising anN-acetylated oligosaccharide, a galacto-oligosaccharide and a sialylatedoligosaccharide to an infant in the first six months of life.
 4. Themethod of claim 1, wherein the N-acetylated oligosaccharide is selectedfrom the group consisting of GalNAcα1,3Galβ1,4Glc,Galβ1,6GalNAcα1,3Galβ1,4Glc and mixtures thereof.
 5. The method of claim1, wherein the galacto-oligosaccharide is selected from the groupconsisting of Galβ1,6Gal, Galβ1,6Galβ1,4Glc Galβ1,6Galβ1,6Glc,Galβ1,3Galβ1,3Glc, Galβ1,3Galβ1,4Glc, Galβ1,6Galβ1,6Galβ1,4Glc,Galβ1,6Galβ1,3Galβ1,4Glc Galβ1,3Galβ1,6Galβ1,4Glc,Galβ1,3Galβ1,3Galβ1,4Glc, Galβ1,4Galβ1,4Glc and Galβ1,4Galβ1,4Galβ1,4Glcand mixtures thereof.
 6. The method of claim 1 wherein the sialylatedoligosaccharide is selected from the group consisting ofNeuAcα2,3Galβ1,4Glc, NeuAcα2,6Galβ1,4Glc and mixtures thereof.
 7. Themethod of claim 2, wherein the N-acetylated oligosaccharide is selectedfrom the group consisting of GalNAcα1,3Galβ1,4Glc,Galβ1,6GalNAcα1,3Galβ1,4Glc and mixtures thereof.
 8. The method of claim3, wherein the N-acetylated oligosaccharide is selected from the groupconsisting of GalNAcα1,3Galβ1,4Glc, Galβ1,6GalNAcα1,3Galβ1,4Glc andmixtures thereof.
 9. The method of claim 2, wherein thegalacto-oligosaccharide is selected from the group consisting ofGalβ1,6Gal, Galβ1,6Galβ1,4Glc Galβ1,6Galβ1,6Glc, Galβ1,3Galβ1,3Glc,Galβ1,3Galβ1,4Glc, Galβ1,6Galβ1,6Galβ1,4Glc, Galβ1,6Galβ1,3Galβ1,4GlcGalβ1,3Galβ1,6Galβ1,4Glc, Galβ1,3Galβ1,3Galβ1,4Glc, Galβ1,4Galβ1,4Glcand Galβ1,4Galβ1,4Galβ1,4Glc and mixtures thereof.
 10. The method ofclaim 3, wherein the galacto-oligosaccharide is selected from the groupconsisting of Galβ1,6Gal, Galβ1,6Galβ1,4Glc Galβ1,6Galβ1,6Glc,Galβ1,3Galβ1,3Glc, Galβ1,3Galβ1,4Glc, Galβ1,6Galβ1,6Galβ1,4Glc,Galβ1,6Galβ1,3Galβ1,4Glc Galβ1,3Galβ1,6Galβ1,4Glc,Galβ1,3Galβ1,3Galβ1,4Glc, Galβ1,4Galβ1,4Glc and Galβ1,4Galβ1,4Galβ1,4Glcand mixtures thereof.
 11. The method of claim 2 wherein the sialylatedoligosaccharide is selected from the group consisting ofNeuAcα2,3Galβ1,4Glc, NeuAcα2,6Galβ1,4Glc and mixtures thereof.
 12. Themethod of claim 3 wherein the sialylated oligosaccharide is selectedfrom the group consisting of NeuAcα2,3Galβ1,4Glc, NeuAcα2,6Galβ1,4Glcand mixtures thereof.